Toyo R888 tyre wear problem - advice needed

[GuyM]

was at silverstone on sat on the National Circuit (which is a cr@p loop - would never have gone if i had known what it was like). Basically a triangle with 3 hard righthanders.

i now have a wear "groove" about 1 inch wide on my front nearside (passenger side) tyre just off center all the way round the tyre.

Now this tyre got a fair bit of hard cornering pushed on it but this is really weird wear.

I was running at 25psi (cold) had no trouble at snetterton last week (clockwise circuit as well) but this wear looks to have sh@gged the tyre a bit.

The car is an '87 325 (familiar to the zone i think) weighing sub 1000kgs and track day speced up - any advice on this uneven wear would really help - i can't afford to knacker tyres like this! tracking/geometry/pressures - any advice really appreciated.

(will be sticking this post on pistonheads to get a bit of input there too, so sorry if people have read it twice!)

[maxfield]

It's not slightly catching on anything in the wing is it?

[GuyM]

hadn't really though of that. everyone says the 325 lump is a bit heavy and i suppose it could push down on the outside corner i guess, so i will go and have a look and see if i can find any offending lumps of rubber on the wheelarch in the daylight

[UweM3]

I have experienced the same at Brands Hatch Indy (left front tyre) and believe that 25psi cold is not enough pressure for this tyre. But that's just my opinion.

[JimmyC]

23psi cold is more than adequate in R888's in dry race conditions, depends how hot you get them and the circuit though- so thats an average/appox before flaming begins

Target is 30 psi hot

hard to tell with out a pic? but the use of the word groove could mean catching something

they tend to wear just off centre, when run with 4/5 degree neg at the above pressures

[GuyM]

i started this same thread on pistoheads for their input - see link below
http://www.pistonheads.com/gassing/topi ... 0&t=461735
and it is interesting to see i am not alone.

the pic someone has put up is almost exactly the wear "groove" that i have if that helps.

it seems like pressure/geometry/camber/alignment could all be factors....but keep your opinions coming please

[UweM3]

i started this same thread on pistoheads for their input - see link below
http://www.pistonheads.com/gassing/topi ... 0&t=461735
and it is interesting to see i am not alone.

the pic someone has put up is almost exactly the wear "groove" that i have if that helps.

it seems like pressure/geometry/camber/alignment could all be factors....but keep your opinions coming please

have a read here, might help
http://www.toyo.com.au/Pit%20Lane.htm#H ... 0Pressures

snip
Camber Settings

Toyo motor sport radials will provide optimum cornering grip with camber settings between negative 3 and 6 degrees on steer axles. Where adjustment is possible, negative camber on drive axles will also improve cornering grip. Optimum camber angles will provide optimum cornering grip, and therefore will be an important contributing factor for improving lap times.
NOTE: On some vehicles a lack of negative camber can over-heat the outside tread shoulder causing grip levels to drop-off suddenly and in some cases cause blistering of the outside tread shoulder. Large heavy, front engine cars are most susceptible to this type of tyre damage.

CAMBER SETTINGS & INFLATION PRESSURES
Where camber adjustment is limited or class rules limit the amount of negative camber allowed, increasing cold inflation pressures may help to prevent the outside tread shoulder over-heating. This also applies to vehicles that are used on the street as well as the track, where the camber settings are a compromise for this dual purpose. Where this is the case, adding 3 - 4psi to recommended cold and hot inflation pressures usually helps to prevent the outside tread shoulder over-heating. Increasing inflation pressures to prevent the outside tread shoulder over-heating where more negative camber is needed for optimum tyre performance and grip is only recommended where camber adjustment is not possible, and is not always effective (testing the pressure increase will confirm wether the increased inflation pressure improves lap times).

[Lloydie38]

I tried the Toyo R888 tyres on my 325 on a really hot day on a disused airfield on the Isle of Man. The grip was great but after 86 hot miles the tyres looked like this.../.

See Pic
[img][img]http://i142.photobucket.com/albums/r117 ... G_2082.jpg[/img][/img]

[JimmyC]

Lyodie, looks like a pretty even wear

I wouldn't be upset by that, I'd be pleased and loads of life in there

As for the uneven wear, have seen that on a set of my tyres I lent to someone at Brands- they had minimal neg camber.

So that maybe worth a look at

[UweM3]

Lyodie, looks like a pretty even wear

I wouldn't be upset by that, I'd be pleased and loads of life in there

As for the uneven wear, have seen that on a set of my tyres I lent to someone at Brands- they had minimal neg camber.

So that maybe worth a look at

Agree, that looks as it should. I just wonder how 6 degree neg camber look like, as per suggestion of Toyo! I have 2.6 (ish) and won't be able to add more with the current suspension.

[JimmyC]

I run at 5 degrees neg, but only have spanking new tyres at the moment

Hope to get on track in December so can get some pics of the wear I get then, I'll see if I can get anything from the other PBMW guys with similar camber

[Lloydie38]

Lyodie, looks like a pretty even wear

I wouldn't be upset by that, I'd be pleased and loads of life in there

As for the uneven wear, have seen that on a set of my tyres I lent to someone at Brands- they had minimal neg camber.

So that maybe worth a look at

Agree, that looks as it should. I just wonder how 6 degree neg camber look like, as per suggestion of Toyo! I have 2.6 (ish) and won't be able to add more with the current suspension.

JimmyC - Even wear - thanks I feel better now

UweM3 - with the 2.6ish neg cam are you using adjustable top mounts? I'm considering some but £245 for Spax ones seems a bit expensive, I don't have coilovers so it's my only real option - unless you know something different...

[JimmyC]

Sure I've mentioned this before, so sorry if I have

Mod the bog standard ones, you can get as much neg with them (probably more) as you can with £250/300 adjustables

Get the BMW accident repair ones and they already have 2 degrees (I think) built into them, so you have less to mod

Your camber will be limited by the spings fouling the turrets though, your ride hieght also is a contributing factor

[UweM3]

the BMW corrections mounts add 0.5 deg
I have made some adjustable mounts using the BMW oem mounts. Very simple and for less than the BMW correction mounts.
I am hoping to get some more made this side of X-mas. £69 the pair (without the BMW rubbermount)

[JimmyC]

similar to how we bodge them in PBMW, just yours are ALOT better looking and engineered

We just chop off one side, weld back on the other and redrill

[UweM3]

similar to how we bodge them in PBMW, just yours are ALOT better looking and engineered

We just chop off one side, weld back on the other and redrill

intention was to have them quick adjustable.
Drive to the track with mount on centre (road setup) jack wheel up and adjust camber to max possible (--> till spring hits the sheetmetal
Before you drive howm, reverse process. Takes 10mins.

Your solution is of course not bad either. For track/race only it dosn't matter how it looks. Form follows function!

[handpaper]

I'm interested in these, Uwe, my kind of mod! Are you just slotting the holes in the OEM top mount? How much camber adjustment is there?

ETA - it looks like about an inch of movement at the top mount, which equates to about 2 degrees extra negative camber - worth having!

Sorry for the hijack, cheapaschips - but I saw something similar on a friend's Scooby. He'd been running his R888s at 30psi cold i.e. far too high a pressure, and had a 'groove' in the middle when the tyre cooled.
I also took my front-left R888 down to the canvas, then to the steel belts when : (1)in Nurburg (2)in sunshine (3) on a Sunday when I couldn't get replacements anywhere

[UweM3]

I'm interested in these, Uwe, my kind of mod! Are you just slotting the holes in the OEM top mount? How much camber adjustment is there?

No there's a bit more involved, just don't want to show all the details

ETA - it looks like about an inch of movement at the top mount, which equates to about 2 degrees extra negative camber - worth having!

approx 1.7

Sorry for the hijack, cheapaschips - but I saw something similar on a friend's Scooby. He'd been running his R888s at 30psi cold i.e. far too high a pressure, and had a 'groove' in the middle when the tyre cooled.
I also took my front-left R888 down to the canvas, then to the steel belts when : (1)in Nurburg (2)in sunshine (3) on a Sunday when I couldn't get replacements anywhere

you need to check hot pressure. pressure build up can vary a lot between cars. (suspension, wheel offset, rim width, brakes, rollbars etc)
I still believe that the Toyo's need up to 40 psi HOT (on the M3 at least), I fellow M3 owner came to the same result, we discovered while chatting in the Ring car park.

[ste]

Ideally chaps you need a pyrometer rather than just guessing at tyre pressures and static camber.

I run -3° static front and rear and with tyres set cold at 20PSI, have 30PSI hot and even wear.

[UweM3]

Ideally chaps you need a pyrometer rather than just guessing at tyre pressures and static camber.

I run -3° static front and rear and with tyres set cold at 20PSI, have 30PSI hot and even wear.

is that with Toyo R888?

[JimmyC]

from experience and testing 3 degrees is not enough on R888's

[handpaper]

PBMW boys are using -4 degrees at the front, AFAIK.
Uwe, ideal pressure will vary according to tyre size, loading and profile. 30psi hot gave me even temperatures across each tyre; they were killed by excess toe-in at the rear, possibly due to worn bushes. You have PM Re the top mounts

[agent006]

No there's a bit more involved, just don't want to show all the details

I was interested too. I guess you're not though....

[UweM3]

No there's a bit more involved, just don't want to show all the details

I was interested too. I guess you're not though....

you can buy a set off me.......

[agent006]

Will need to know more details for that...

[UweM3]

Will need to know more details for that...

haha, good one

what do you need to know? The mounts will centre itself to the stock position and you can adjust as much camber till the spring hit the sheetmetal of the strut tower.

I am running a set 2 years+ with many track days and Nuerburgring.

I have sold several sets and none came back faulty and everybody is very pleased with the ease of use and the value for money.

[agent006]

haha, good one

Your kit sounds interesting, but i don't want to play games of wit to get parts for my car, so i'll leave them.

[UweM3]

haha, good one

Your kit sounds interesting, but i don't want to play games of wit to get parts for my car, so i'll leave them.

I am not trying to play games but previous experience with beeing all to open has resulted in copied parts offered by someone else.
I don't mind sharing stuff, but when I have put time and effort (and money!) towards it, I just want to see the rewards.

[paulg390]

Was good to meet you at the weekend and see our old motor still pulling like a train !
We have seen these issues on ours too and so have played with temps and camber (now run 26 deg cold, and about 3 deg negative front) and so far so good. However, can't be sure as we were using 888s in the damp and slicks in the dry on Saturday and so can't really say but they looked ok at the end...
Will keep you posted

[GuyM]

cheers paulg390 - thought i would run into someone who know a bit about my car sooner or later - some of its last 12 owners had to be zoners who had moved onto better e30s!

right people, lots of interesting info coming back and i am learning all the time. i think the following 3 points have come out of it for me:

1 - tyre pressures. i am just going to have to keep playing around until i get what works best for me.

2 - negative camber. this seems the most likely solution but trying to run a car on >5 neg camber is going to cost a bit to set up - and kill the tyres to and from the track. But i take your point about cheap 14" steelies to and from the track then decent track tyres once i get there. (and yes "iguana" it's good to know someone has the same nasty alloys as me - i kept them because their design allows me to look closely at the sides of the brake pads to see what sort of wear i have got left! - no chance of seeing anything with cross-spokes and i don't rely on dodgy electronic gizmos like brake pad wear/warning sensors - far to high tec for my 20 year old heap)

3 - driving style. this is one i can probably do the most about to reduce the front tyre wear. like many track dayers i don't brake hard enough for a corner, carry too much speed into it then find i am scrubbing off speed, almost understeering and putting too much pressure on the front outside tyre as i go round the corner and drift too wide. what i need to learn to do is brake much later, brake much harder, turn in quicker (get the back end out a bit if i can) and then get on the power at the right time in the corner/exit to prevent oversteer. i guess i really shouldn't have much excuse in a RWD BMW but heh, i'm still learning. i will be at Rockingham on Sat so any advice then will be much appreciated - mine is the tatty blue e30 with no bumpers and nasty 5 spoke alloys!

I am still yet to talk to a Toyo technician although i have been recommended to and i will just as soon as i can get through, just to get their take on it.

[JimmyC]

Alan Meaker from Toyo is currently on holiday and is the guy that advises us in PBMW, I would suguest speaking with him when he returns

I can send you his number tomorrow as its at work.

I am speaking with someone else there tomorrow about PBMW so can see if anyone else can help, but alan does know e30s and he has taken loads of data from our cars

[GuyM]

cheers JimmyC.
it was Alan's details i was given - yes it goes into ansaphone so i'll try him next week

[iguana]

uwe- id be interested in a set of yr top mounts bud, if you can tell me what sort of camber i can get max- only pain is im on coventional spring sizes- eibach pros linked to Koni t/a's, not coilies, so may restrict the camber I can get

Cheapychippy- youve missed out spring rates bud, the racers run much higher rates than you'll get in typical coilover or sepretates spring set- easily double the lbs rates makes a lot of diference, as i found with yrs of tracking Golfs

[Francisco]

I'm running Uwe's camber plates and I definately recommend them. Easily reversible, the rubber keeps the car civilized when running over potholes and VERY reasonbly priced.

P.S. I run 888's at an optimum 38 psi. BTW, tyre temperature should NOT be the same across the tyre there should be a 10º diference on the outer edge.

[handpaper]

Is that 38 psi hot or cold? Best pressure for R888s in 205/50/15 seems to be 30-32 psi hot.
At that pressure you'll see 10º (or more) cooler on the edges than the centre, but I don't agree that that's a good thing.
Tyre surface temperature is a function of stress; even distribution of that stress provides best grip and least wear.